Add. `find_ca_bundle` function to `cURL.utils` module to find curl-ca-bundle.crt file

.travis.yml

@@ -26,6 +26,7 @@ install:
 
 script: 
   - cd test
+  - lua -e "print(require 'cURL.utils'.find_ca_bundle())"
   - lunit.sh test_easy.lua
   - lunit.sh test_safe.lua
   - lunit.sh test_form.lua

rockspecs/lua-curl-scm-0.rockspec

@@ -59,6 +59,7 @@ build = {
   modules = {
     ["cURL"           ] = "src/lua/cURL.lua",
     ["cURL.safe"      ] = "src/lua/cURL/safe.lua",
+    ["cURL.utils"     ] = "src/lua/cURL/utils.lua",
     ["cURL.impl.cURL" ] = "src/lua/cURL/impl/cURL.lua",
 
     lcurl = {

src/lua/cURL/utils.lua

@@ -0,0 +1,69 @@
+--- Returns path to cURL ca bundle
+--
+-- @tparam[opt="curl-ca-bundle.crt"] string name name of bundle
+-- @treturn string path to file (CURLOPT_CAINFO)
+-- @treturn string path to ssl dir path (CURLOPT_CAPATH)
+--
+-- @usage 
+--  local file, path = find_ca_bundle()
+--  if file then e:setopt_cainfo(file) end
+--  if path then e:setopt_capath(path) end
+--
+local function find_ca_bundle(name)
+  name = name or "curl-ca-bundle.crt"
+
+  local path  = require "path"
+  local env   = setmetatable({},{__index = function(_, name) return os.getenv(name) end})
+
+  local function split(str, sep, plain)
+    local b, res = 1, {}
+    while b <= #str do
+      local e, e2 = string.find(str, sep, b, plain)
+      if e then
+        table.insert(res, (string.sub(str, b, e-1)))
+        b = e2 + 1
+      else
+        table.insert(res, (string.sub(str, b)))
+        break
+      end
+    end
+    return res
+  end
+
+  if env.CURL_CA_BUNDLE and path.isfile(env.CURL_CA_BUNDLE) then
+    return env.CURL_CA_BUNDLE
+  end
+
+  if env.SSL_CERT_DIR and path.isdir(env.SSL_CERT_DIR) then
+    return false, env.SSL_CERT_DIR
+  end
+
+  if env.SSL_CERT_FILE and path.isfile(env.SSL_CERT_FILE) then
+    return env.SSL_CERT_FILE
+  end
+
+  if not path.IS_WINDOWS then return end
+
+  local paths = {
+    '.',
+    path.join(env.windir, "System32"),
+    path.join(env.windir, "SysWOW64"),
+    env.windir,
+  }
+  for _, p in ipairs(split(env.path, ';')) do paths[#paths + 1] = p end
+
+  for _, p in ipairs(paths) do
+    p = path.fullpath(p)
+    if path.isdir(p) then
+      p = path.join(p, name)
+      if path.isfile(p) then
+        return p
+      end
+    end
+  end
+end
+
+return {
+  find_ca_bundle = find_ca_bundle;
+}
+